title: Choosing among generalized linear models applied to medical data.
abstract: When testing for a treatment effect or a difference among groups, the distributional assumptions made about the response variable can have a critical impact on the conclusions drawn. For example, controversy has arisen over transformations of the response (Keene). An alternative approach is to use some member of the family of generalized linear models. However, this raises the issue of selecting the appropriate member, a problem of testing non-nested hypotheses. Standard model selection criteria, such as the Akaike information criterion (AIC), can be used to resolve problems. These procedures for comparing generalized linear models are applied to checking for difference in T4 cell counts between two disease groups. We conclude that appropriate model selection criteria should be specified in the protocol for any study, including clinical trials, in order that optimal inferences can be drawn about treatment differences.
authors.affiliation: Department of Medical Statistics, School of Computing Sciences, De Montfort University, Leicester, U.K.
authors.forename: J K
authors.initials: JK
authors.lastname: Lindsey
authors.forename: B
authors.initials: B
authors.lastname: Jones
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods*; D003657:Decision Making; D006689:Hodgkin Disease / Q000097:blood; D006801:Humans; D016014:Linear Models; D018655:Lymphocyte Count; D012107:Research Design